Subtract 21/36 from 70/21, Solve 3 7/21

Subtract 21/36 from 70/21

1^st number: 3 7/21, 2^nd number: 21/36

70/21 - 21/36 is 11/4.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 21 × 12 = 252,
70/21 = 70 × 12/21 × 12 = 840/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252
Subtract the two like fractions:
840/252 - 147/252 = 840 - 147/252 = 693/252
After reducing the fraction, the answer is 11/4
In mixed form: 23/4

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